WARNING“Quick-charging” the vehicle battery is dangerous and requires a special
charger and specialist knowledge.
CAUTION
On vehicles with the START/STOP system, the pole terminal of the charger must
not be connected directly to the negative terminal of the vehicle battery, but only
to the engine earth » page 244, Jump-starting in vehicles with the START-STOP
system .
Note
We therefore recommend that vehicle batteries be rapid charged by a specialist
garage.
Replacing
First read and observe the introductory information and safety warn-
ings
on page 224.
When replacing a battery, the new vehicle battery must have the same capacity,
voltage, amperage and be the same size. Suitable vehicle battery types can be
purchased from a specialist garage.
We recommend having the battery replaced by a specialist garage, where the
new vehicle battery will be installed properly and the original battery will be dis-
posed of in accordance with national regulations.
Disconnecting and reconnecting
First read and observe the introductory information and safety warn-
ings
on page 224.
On disconnecting and reconnecting the vehicle battery, the following functions
are initially deactivated or are no longer able to operate fault-free:
OperationOperating measureElectrical power window (operational faults)» page 49Enter the radio/navigation system code num-
ber» Operating instructions for Info-
tainment Radio or » Operating
instructions for Infotainment
NavigationSetting the clock» page 14Data in the multifunction display are deleted» page 29
Note
We recommend having the vehicle checked by a specialist garage in order to en-
sure full functionality of all electrical systems.
Automatic load deactivation
First read and observe the introductory information and safety warn-ings
on page 224.
The vehicle voltage control unit automatically prevents the battery from discharg-
ing when the bettery is subjected to heavy loads. This manifests itself by the fol-
lowing.
› The idling speed is raised to allow the generator to deliver more electricity to
the electrical system.
› Where appropriate large convenience consumers, e.g. seat heaters, rear win-
dow heaters, have their power limited or in case of emergency shut off com-
pletely.
CAUTION
■ Despite such intervention by the vehicle electric system management, the vehi-
cle battery may be drained. For example, when the ignition is switched on a long
time with the engine turned off or the side or parking lights are turned on during longer parking.■
Consumers which are supplied via a 12 V socket can cause the vehicle battery to
discharge when the ignition is switched off.
Note
Driving comfort is not disrupted by any shutting off of consumers. Often the driv-
er is not aware of it having taken place.
227Inspecting and replenishing
